max/A LI )iĞ;i i YDK ( ; RKKN 215
heated. An orange-coloured oil passes over, which crystallises
in the receive1!*. The distillation is continued until the distillate ,
no longer solidifies on cooling. A black, resinous mass remains
in the retort. The crude triphenyl methane in the receiver is
recrystallised from hot ben/ene, with which it forms-ia crystal- , , i
line com])ound of the formula C^H^.C,;]"!,;. This is again
crystallised. By heating the substance on the water-bath it
loses benzene, and the hydrocarbon is finally crystallised from
hot alcohol. Yield, 25 30 grains.
Ci U.'l;, ~h 3C,}M,i - CI !(C(iH,), + 3HC1. ! '
/>;v>/v.r//V.y. Colourless plates ; in. p. 92" ; b. p. 360°. ,
AYfir/vVw.v. Synthesis of Pararosaniline.- Dissolve a
gram of the hydrocarl)on in about 5 c.c. cold fuming nitric acid, '
pour into water, filler, wash, dry on porous plate, and dissolve in
5 c.c. glacial acetic acid. Add a. grain of zinc dust on the point
of a knife gradually, and shake up. The colour changes to brown,
and the leuco-base of pararosaniline is formed. It is diluted II*
with water and precipitated by ammonia. It is then filtered and ']
dried. < )n gently warming the dry precipitate with a. few drops
of concentrated hydrochloric, acid in a porcelain basin and then .,,
diluting with water, a magenta colouration is produced from the jiffl
formation of pararosaniline' hydrochloride (E. and O. Fischer). 'wi
Sec Appendix, p. 312, Jt[
Benzaldehyde Green (Malachite Green) , \ ]
(Telramethyldiaminotriphenylmethane), *' '
/<-'o Mr, V I
('). Kischer, Anmilen, 1883, 217, 250, 262. ^ |!
50 grins, dimethyl'miline. l\
20 ben/a.ldchycle. -1
40 xinc chloride (fused and powdered;. ^
A mixture of the above is heated on the water-bath in a. \^
porcektin basin until the smell of benxaldehyde has disappeared %V